Letter to the editor, Re: Clark, P, (2021) Improvements to the Observational Method in New South Wales Road Tunnel Construction, Australian Geomechanics Society, Sydney Chapter Symposium, November 2021, pp 89-98

Robert Bertuzzi, Andrew de Ambrosis, David Oliveira, Thomas Roper, Mark Trim and Christian Bodner

In his paper at the Australian Geomechanics Society Sydney Chapter 2021 Symposium, Clark (2021) suggests improvements in applying the Observation Method (OM) to tunnelling in Sydney. The authors would like to thank Mr Clark for raising a number of clearly very important issues in his publication which warrant further examination. Whilst views and opinions amongst professionals will sometimes differ, it is acknowledged that no process is ever perfect and as representatives of various design organisations, we want to respond to some of the discussion points raised. An investigation into the improvements of the observational method for Road Tunnel Construction is an important matter and we value the opportunity to share further discussion points on this topic.